If you have multiple names on the will you should consider what happens when one of the people dies. Do you want the property to be probated (go via intructions in the will) or immediately passed on to the surviving owner. In case one a lawyer probably has to get involved with the appropriate costs.
You could also have a trust buy the property with you and your son having appropriate powers over the trust and get the same benefit avoiding probate entirely. Each way has advantages and should be discussed with someone knowledgeable in these things.